A team of scientists at Stanford University has developed a tactile sensing system which could produce the human sensation of touch.
According to the research published in the Science, the sensing system or artificial skin could one day permit people with prostheses to feel the sense of touch with their artificial limbs.
‘Artificial Skin Capable of Sensing the Pressure of Touch has been developed at Stanford University using a two ply printed plastic construct. The upper layer serving as a sensing platform and the lower layer being a circuit for converting touch into digital signals.’
The research was led by Prof. Zhenan Bao of the University.
Human skin depends on cutaneous receptors that generate digital signals for tactile sensing in which the intensity of stimulation is changed to a series of voltage pulses. The team, in the journal, presented a power-efficient skin-inspired mechanoreceptor with a flexible organic transistor circuit. They say that the circuit transduces pressure into digital frequency signals directly.
The output frequency stands between 0 and 200 hertz, with a sublinear response to increasing force stimuli that mimics slow-adapting skin mechanoreceptors. (Mechanoreceptors are generally a sensory receptor that responds to mechanical pressure or distortion).
The output of the sensors was then utilized to stimulate optogenetically engineered mouse somatosensory neurons of mouse cortex (in vitro) attaining stimulated pulses in accordance with pressure levels. Researchers wrote that the study represents a step toward the design and use of large-area organic electronic skins with neural-integrated touch feedback for replacement limbs.